How do you expect them to serve you ads? They have to get to your phone _somehow_ so there will always be network overhead. The amount of network overhead can

How do you expect them to serve you ads? They have to get to your phone _somehow_ so there will always be network overhead. The amount of network overhead can vary wildly. If the app is polling the ad network API on startup and at a fixed interval, it can keep the radio awake for longer than it would otherwise, or wake it up and keep it in a high power state for the duration of the CELL_DCH timer. It's not an impossible requirement to queue ads, reduce the frequency of polling, and coalesce the ad network API calls with other app network traffic.